[balsa] Guard against mailbox changes

[Peter Bloomfield <peterb src gnome org>]

commit d9b18d2356ccb1620e59bc90293516da5313f174
Author: Peter Bloomfield <PeterBloomfield bellsouth net>
Date:   Fri Jan 10 15:26:59 2020 -0500

    Guard against mailbox changes
    
    Guard against mailbox being closed or finalized during a call to
    libbalsa_progress_set_fraction().
    
    * libbalsa/mailbox.c (lbm_run_filters_on_reception_idle_cb):
    * libbalsa/mailbox_local.c (lbm_local_update_view_filter),
      (libbalsa_mailbox_local_prepare_threading):

 ChangeLog                |  9 +++++++++
 libbalsa/mailbox.c       | 25 ++++++++++++++++++++-----
 libbalsa/mailbox_local.c | 10 +++++++---
 3 files changed, 36 insertions(+), 8 deletions(-)
---
diff --git a/ChangeLog b/ChangeLog
index 51c1aa86d..ff69f0ae2 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,12 @@
+2020-01-10  Peter Bloomfield  <pbloomfield bellsouth net>
+
+       Guard against mailbox being closed or finalized during a call to
+       libbalsa_progress_set_fraction().
+
+       * libbalsa/mailbox.c (lbm_run_filters_on_reception_idle_cb):
+       * libbalsa/mailbox_local.c (lbm_local_update_view_filter),
+       (libbalsa_mailbox_local_prepare_threading):
+
 2020-01-09  Peter Bloomfield  <pbloomfield bellsouth net>
 
        mailbox: Check whether the mailbox was closed during
diff --git a/libbalsa/mailbox.c b/libbalsa/mailbox.c
index 0fb2594f0..d595f7508 100644
--- a/libbalsa/mailbox.c
+++ b/libbalsa/mailbox.c
@@ -842,6 +842,8 @@ lbm_run_filters_on_reception_idle_cb(LibBalsaMailbox * mailbox)
     guint total;
     guint progress_total;
     LibBalsaProgress progress;
+    gboolean is_mailbox = TRUE;
+    gboolean is_open = TRUE;
 
     libbalsa_lock_mailbox(mailbox);
 
@@ -923,21 +925,34 @@ lbm_run_filters_on_reception_idle_cb(LibBalsaMailbox * mailbox)
                                                /
                                                ((gdouble) progress_total));
                 /* mailbox could have been closed during set-fraction */
-                if (priv->state != LB_MAILBOX_STATE_OPEN)
+                if (!LIBBALSA_IS_MAILBOX(mailbox))
+                    is_open = is_mailbox = FALSE;
+                else if (!LIBBALSA_MAILBOX_OPEN(mailbox))
+                    is_open = FALSE;
+
+                if (!is_open)
                     break;
             }
         }
         libbalsa_mailbox_search_iter_unref(search_iter);
 
-        libbalsa_mailbox_register_msgnos(mailbox, msgnos);
-        libbalsa_filter_mailbox_messages(filter, mailbox, msgnos);
-        libbalsa_mailbox_unregister_msgnos(mailbox, msgnos);
+        if (is_open) {
+            libbalsa_mailbox_register_msgnos(mailbox, msgnos);
+            libbalsa_filter_mailbox_messages(filter, mailbox, msgnos);
+            libbalsa_mailbox_unregister_msgnos(mailbox, msgnos);
+        }
+
         g_array_free(msgnos, TRUE);
+
+        if (!is_open)
+            break;
     }
     libbalsa_progress_set_text(&progress, NULL, 0);
 
     g_slist_free(filters);
-    libbalsa_unlock_mailbox(mailbox);
+
+    if (is_mailbox)
+        libbalsa_unlock_mailbox(mailbox);
 
     return FALSE;
 }
diff --git a/libbalsa/mailbox_local.c b/libbalsa/mailbox_local.c
index 39e2a396c..8ef0e5e88 100644
--- a/libbalsa/mailbox_local.c
+++ b/libbalsa/mailbox_local.c
@@ -1270,13 +1270,15 @@ lbm_local_update_view_filter(LibBalsaMailbox * mailbox,
                                           FALSE);
         libbalsa_progress_set_fraction(&progress, ((gdouble) msgno) /
                                        ((gdouble) total));
+        if (!LIBBALSA_IS_MAILBOX(mailbox) || !MAILBOX_OPEN(mailbox))
+            break;
     }
     libbalsa_progress_set_text(&progress, NULL, 0);
     libbalsa_mailbox_search_iter_unref(iter_view);
 
     /* If this is not a flags-only filter, the new mailbox tree is
      * temporary, so we don't want to save it. */
-    if (is_flag_only)
+    if (is_flag_only && LIBBALSA_IS_MAILBOX(mailbox))
         lbm_local_queue_save_tree(LIBBALSA_MAILBOX_LOCAL(mailbox));
 }
 
@@ -1360,7 +1362,7 @@ libbalsa_mailbox_local_prepare_threading(LibBalsaMailbox * mailbox,
             libbalsa_progress_set_fraction(&progress,
                                            ((gdouble) msgno) /
                                            ((gdouble) (total - start)));
-            if (!MAILBOX_OPEN(mailbox)) {
+            if (!LIBBALSA_IS_MAILBOX(mailbox) || !MAILBOX_OPEN(mailbox)) {
                 /* Mailbox was closed during set-fraction. */
                 retval = FALSE;
                 break;
@@ -1380,7 +1382,9 @@ libbalsa_mailbox_local_prepare_threading(LibBalsaMailbox * mailbox,
                 g_idle_add((GSourceFunc) lbm_local_thread_idle, local);
         }
     }
-    libbalsa_unlock_mailbox(mailbox);
+
+    if (LIBBALSA_IS_MAILBOX(mailbox))
+        libbalsa_unlock_mailbox(mailbox);
 
     return retval;
 }